例如,在输入框中给定两个日期:

<input id="first" value="1/1/2000"/>
<input id="second" value="1/1/2001"/>

<script>
  alert(datediff("day", first, second)); // what goes here?
</script>

如何在JavaScript中获得两个日期之间的天数?


当前回答

function formatDate(seconds, dictionary) {
    var foo = new Date;
    var unixtime_ms = foo.getTime();
    var unixtime = parseInt(unixtime_ms / 1000);
    var diff = unixtime - seconds;
    var display_date;
    if (diff <= 0) {
        display_date = dictionary.now;
    } else if (diff < 60) {
        if (diff == 1) {
            display_date = diff + ' ' + dictionary.second;
        } else {
            display_date = diff + ' ' + dictionary.seconds;
        }
    } else if (diff < 3540) {
        diff = Math.round(diff / 60);
        if (diff == 1) {
            display_date = diff + ' ' + dictionary.minute;
        } else {
            display_date = diff + ' ' + dictionary.minutes;
        }
    } else if (diff < 82800) {
        diff = Math.round(diff / 3600);
        if (diff == 1) {
            display_date = diff + ' ' + dictionary.hour;
        } else {
            display_date = diff + ' ' + dictionary.hours;
        }
    } else {
        diff = Math.round(diff / 86400);
        if (diff == 1) {
            display_date = diff + ' ' + dictionary.day;
        } else {
            display_date = diff + ' ' + dictionary.days;
        }
    }
    return display_date;
}

其他回答

我也有同样的问题,但如果你在SQL查询上做的话会更好:

DateDiff(DAY, StartValue,GETDATE()) AS CountDays

查询将自动生成一个列CountDays

下面的解决方案将假设这些变量在代码中可用:

const startDate  = '2020-01-01';
const endDate    = '2020-03-15';

原生 JS

步骤:

设定开始日期 设定结束日期 计算的区别 将毫秒转换为天

const diffInMs   = new Date(endDate) - new Date(startDate)
const diffInDays = diffInMs / (1000 * 60 * 60 * 24);

备注:

我知道这不是你问题的一部分,但一般来说,我不建议在香草JavaScript中做任何日期计算或操作,而是使用date-fns, Luxon或moment.js这样的库,因为有许多边缘情况。

这个简单的JavaScript回答以十进制数计算天数。此外,在使用夏令时时,它可能会遇到边缘情况


使用图书馆

- 日期-fns

const differenceInDays = require('date-fns/differenceInDays');
const diffInDays = differenceInDays(new Date(endDate), new Date(startDate));

文档:https://date-fns.org/v2.16.1/docs/differenceInDays

——国际光子

const { DateTime } = require('luxon');
const diffInDays = DateTime.fromISO(endDate).diff(DateTime.fromISO(startDate), 'days').toObject().days;

文档:https://moment.github.io/luxon/docs/class/src/datetime.js DateTime.html # instance-method-diff

——Moment.js

const moment = require('moment');
const diffInDays = moment(endDate).diff(moment(startDate), 'days');

文档:https://momentjs.com/docs/ / /显示/不同


RunKit示例

夏令时问题使这里的许多答案无效。我将使用一个helper函数来获得给定日期的唯一天数——通过使用UTC方法:

const dayNumber = a => Date.UTC(a.getFullYear(), a.getMonth(), a.getDate()) / (24*60*60*1000); const daysBetween = (a, b) => dayNumber(b) - dayNumber(a); // Testing it const start = new Date(1000, 0, 1); // 1 January 1000 const end = new Date(3000, 0, 1); // 1 January 3000 let current = new Date(start); for (let days = 0; current < end; days++) { const diff = daysBetween(start, current); if (diff !== days) throw "test failed"; current.setDate(current.getDate() + 1); // move current date one day forward } console.log("tests succeeded");

我在Angular中也遇到了同样的问题。我复制了一份,否则他会覆盖第一次约会。两个日期的时间都必须为00:00:00(显然)

 /*
* Deze functie gebruiken we om het aantal dagen te bereken van een booking.
* */
$scope.berekenDagen = function ()
{
    $scope.booking.aantalDagen=0;

    /*De loper is gelijk aan de startdag van je reservatie.
     * De copy is nodig anders overschijft angular de booking.van.
     * */
    var loper = angular.copy($scope.booking.van);

    /*Zolang de reservatie beschikbaar is, doorloop de weekdagen van je start tot einddatum.*/
    while (loper < $scope.booking.tot) {
        /*Tel een dag op bij je loper.*/
        loper.setDate(loper.getDate() + 1);
        $scope.booking.aantalDagen++;
    }

    /*Start datum telt natuurlijk ook mee*/
    $scope.booking.aantalDagen++;
    $scope.infomsg +=" aantal dagen: "+$scope.booking.aantalDagen;
};

一行代码和小代码

const diff=(e,t)=>Math.floor((new Date(e).getTime()-new Date(t).getTime())/1000*60*60*24);

// or

const diff=(e,t)=>Math.floor((new Date(e)-new Date(t))/864e5);

// or

const diff=(a,b)=>(new Date(a)-new Date(b))/864e5|0; 

// use
diff('1/1/2001', '1/1/2000')

为打印稿

const diff = (from: string, to: string) => Math.floor((new Date(from).getTime() - new Date(to).getTime()) / 86400000);